Hand tool



Aug. 16, 1949. s; v. CARLsEN 2,4789894 HAND TOOL Filed April 25, 1946EiELlFuj V. EAFxLTp-I N MOI/MM2,

Patented Aug. 16, 1949 UNITETD STATES PATENT OFFICE .l j 2,478,894 I A;f y. HAND 'r'ooL l sigmacsr1stenmcn ont AppelationV April 25, 194s,'serial No. 664,867 rolim. (c1. :essa-3cr. (Granted, under `the act ofMarch 3, 71883, as

The invention describedherein may be manufactured and used by or for theGoverment for governmental ,pnrtmses, without. the, payment to me of anyroyalty' thereon.,` v Y .Y

invention, relates to an improvement in amended April 30, 19285D3711 Q.G1 7,57)

hand tools such as one for intermittently rotatrock drills or the likewhen struckl a blow on the end of a. handle,l and more particularly theidea of turning the drill, bitY through the proper angle` after eachstroke.` Y

In drilling holes in stone, concrete', or' like majterialsit isnecessary to. rotate the drill after each stroke of the hammer since thedrill used acting as a chisel, and in Qrdferf t9 have Vit pel-'form inits proper function, that is, to cut or chip a hole in the material,` itmust ibe rotated if the cutting edges are to chipor cut off the materialbit by bit. This rotation mayV bedone by hand or mechanically. In orderto obviate the necessity of hand rotation, various forms of mechanicalrotating drills have been tried out, most of the methods taught. howeverbeing applicable only to power driven drills. Someof these require theuse of a hand operated rotation wrench in. order to accomplish thisfunction. In all known embodiments, the rotation depends. largely uponthe down or vpower stroke with its attendantshock to the mechanism orthe operator, andfnone` of the methods pointed' out arereadily adaptablefor use ina drilling tool' powered by hand where the usual Vpractice isto secure the drill withinA the chuck and revolve the entire tool byhand after each stroke, a practice which not only slows up the workbeing done but which is also fatiguing to the operator.

The principal object of my invention is to provide a hand tool whereby adrill may be. rotated mechanically by means of the up stroke of thetool.

A further object of my invention is to provide a hand tool for use witha drill whereby the chuck is rotated through a one-way clutch with amini'- rnum of shock to themechanism.

Another object of my invention is to provide a hand tool which may beapplicable to any tool where a step-by-step rotation of a chu-ck isemployed. I

Other objects and advantages of the invention will become apparentduring the course of the following specication, and the accompanyingdrawings, forming part of the specification, wherein like numbers areused to designate like parts.

In the drawings:

Figure 1 is a fragmentary section, partly in elevation, of the hand toolof this invention,

Figure 2 is an exploded view of the same,

Figure 3 is a transverse section taken on the line 3 3 of Figure 1,

Figure 4 is a longitudinal sectionof a remova- Y 2 ble. barrelfor theshaft, in elevation, and,

Figure 5 is; an end view of the same.v f Referring nowin details to thedraw-ings, th

the shaft being shown .numeral-6 denotes: a.- hand tool which;r actsupon a drill 'lthrough av chuck 8; to rotate. the drill. The .chuck 8 isreceived slidably in the-hollow recess of a handle Hl.

The chuck 8. is generally cylindrical shape andis taperedat.V one` endtoprovide a face tt at relatively smaller diameter than the bod-y, anaisprovidedwith an axial bore Iz in the face end providing a socket for thedrillvlf, saidfgbore being of such depth and-diameter as willaccommodate astand-ard drill. A transverse opening I3 isr providedadjacent the inner end of the bore l2 to facilitate removal ofthe drilll, and the edgev of the face ll adjacent. the tapered side isronnded asindicated in Figure V1l at I4.

, The other end oil the said chuck-8 is' provided with. an axial here;F5; to slidably engage the barrel I 6,V of av shaft tlf, the said barrelIBbeing formed integral with the shaft. I'E. The, bottom of the said:bore l5, provides a striking surface I8 for transmittingV theimpactforoe or theshart If'l. A threaded portion Ill backed by a.shoulder 2o is. provided topermit a. nut 21g-having an opening 2-2therethrough for passage of the: shaft III,A and serving as, aguide forthe barrel l'', to be securely threaded into.y chuck:

The handle I'I'l is generally cylindrical in cross section, and is boredat one end to provide the hollow .recess 9 in which the chuck 8 and thenut 2I are slidably engaged. An axially bored recess 23 of slightlylarger diameter than the shaft I'I to slidably engage the said shaft I1,and in which the said shaft I1 reciprocates, communicates with therecess 9 and extends longitudinally of the said handle to a point nearthe other end thereof, the said other end being closed. The outerdiameter of the handle is reduced lbeyond the recess 9 for convenientgripping within the hand of the operator, its outer surfa-ce beingknurled to provide a secure grip.

The barrel I6 of the shaft I 'l is arranged with a longitudinal cut-outportion 24 to provide housing for a roller member 25, said roller member25 being adapted to bear against the sides of the said cut-out portionand the inner surface of the bore I5. The shaft I1 is also provided witha helical slot 26 to receive a pin 21 adapted to move longitudinallydownward of said shaft I1 within the said slot 26 during the down strokeof the handle I0, the said pin being secured to the saidY handle I 0 inoppositely opposed openings 28 in the reduced portion thereof. A helicalcompression spring 29 is positioned within the bore y23 in the handle I0adjacent the closed end thereof, the said spring being seated betweenthe tera ward under the force of the blow and against the resistance ofthe spring 29 until the bottom 31 of recess 9 strikes against the nut 2|which fits securely in the chuck 8. The kinetic energy ofthe strikingelement is imparted 'through' the said nut to the chuck 8, and in turnto theV drill 1' through its association with the said chuck.

As the handle I moves downward under the` force of the blow, the pin 21is carried downward in the helical slot 26 by the said handle, so thatas the handle-moves axially ldownward, the shaft rotates through alimited angle inY a counter clockwise direction.V Theroller 25, inassociation with the cut out portion`24, constitutes a oneway clutch 38.As theha'ndle movesdown, the shaft l1 moves counter clockwise and thereis no appreciable engagement of roller with the side of the bore l5. Asthe handle is moved upwardly, shaft I1 moves clockwise and roller 25 iscrowded against the sidefof bore l5, thereby causing the chuck to rotateone-eighth of a turn. The'drill 1 is then in proper angular positionforthe next stroke. With each recurring blow the drill is similarlyrotated, Vand through this step-by-step rotation it avoids striking thesame place twice in succession. Y 1

In the modification shown in Figures 4 and 5, a separate andremovablebarrel 30 is provided for the shaft i1 in place of the'- integral formedbarrel I6. Barrel 30 is provided with a-'bore 3| to receive the shaft I1and an internally threaded recess 32 to receive in threaded engagement aset screw 33 which bears against the key 34 adapted to be engaged in akey way formed in the shaft I1. The barrel30 is provided with a cut-outportion 36 similar to the cut-out portion 24 in the barrel I6 to receivethe roller 25. Inrall other respects the barrel 30 functions incooperation with the shaft l1 and the handle I0 in the same manner asalready described.

4 It is to be understood that the form of invention herewith shown is tolbe taken as a preferred example of the same, and that variousmodifications may be made in the combination and arrangement of partsdisclosed in the drawings accompanying the invention without departingfrom the spirit thereof, as defined in the claim annexed hereto.

Having thus described my invention, I claim: An automatically rotatedhand rock drill of the type adapted to be struck by a hammer, comprisinga tubular handle closed at one end, a shaft mounted in said handle forlimited axial and rotational movement therein, a spring in said handlebearing on said shaft and compressed to -continually urge said handleand shaft apart in an axial direction, a cam and follower on said shaftand handle respectively, arranged to convert limited axial relativemovement of said shaft and handle into limited helical relative motion,a

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 490,152 Macomber Jan. 17, 1893670,543 Paulson Mar. 26, 1901 739,440 Oldham Sept. 22, 1903 1,034,010Gilman July 30, 1912 1,555,939 Brisbois Oct. 6, 1925 1,716,114 ChapmanJune 4, 1929 1,934,252

Baker NOV. 7, 1933

